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bios/main: Test down to latency = 3, working.

This commit is contained in:
Florent Kermarrec 2024-04-15 12:06:49 +02:00
parent a95f1b8486
commit 93f76ede95
1 changed files with 30 additions and 4 deletions
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34
litex/soc/software/bios/main.c
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@ -177,13 +177,25 @@ __attribute__((__used__)) int main(int i, char **c)
#ifdef CSR_HYPERRAM_BASE
/* HyperRAM Configuration */
uint16_t config_reg_0 = 0x8f2f;
uint16_t config_reg_0;
hyperram_latency_write(7);
hyperram_reg_control_write(
0 << CSR_HYPERRAM_REG_CONTROL_WRITE_OFFSET |
1 << CSR_HYPERRAM_REG_CONTROL_READ_OFFSET |
2 << CSR_HYPERRAM_REG_CONTROL_ADDR_OFFSET
);
while ((hyperram_reg_status_read() & (1 << CSR_HYPERRAM_REG_STATUS_READ_DONE_OFFSET)) == 0);
config_reg_0 = hyperram_reg_rdata_read();
printf("Configuration Register 0 prev : %08lx\n", config_reg_0);
config_reg_0 &= ~(0b1 << 3); /* Enable Variable Latency */
config_reg_0 &= ~(0b1111 << 4); /* Clear Initial Latency */
config_reg_0 |= (0b0010 << 4); /* Initial Latency of 7 */
//config_reg_0 |= (0b111 << 12); /* 19 ohm */
printf("Configuration Register 0 new : %08lx\n", config_reg_0);
//config_reg_0 |= (0b0010 << 4); /* Initial Latency of 7 */
//config_reg_0 |= (0b0001 << 4); /* Initial Latency of 6 */
//config_reg_0 |= (0b0000 << 4); /* Initial Latency of 5 */
//config_reg_0 |= (0b1111 << 4); /* Initial Latency of 4 */
config_reg_0 |= (0b1110 << 4); /* Initial Latency of 3 */
printf("Configuration Register 0 update : %08lx\n", config_reg_0);
hyperram_reg_wdata_write(config_reg_0);
hyperram_reg_control_write(
1 << CSR_HYPERRAM_REG_CONTROL_WRITE_OFFSET |
@ -191,6 +203,20 @@ __attribute__((__used__)) int main(int i, char **c)
2 << CSR_HYPERRAM_REG_CONTROL_ADDR_OFFSET
);
while ((hyperram_reg_status_read() & (1 << CSR_HYPERRAM_REG_STATUS_WRITE_DONE_OFFSET)) == 0);
//hyperram_latency_write(7);
//hyperram_latency_write(6);
//hyperram_latency_write(5);
//hyperram_latency_write(4);
hyperram_latency_write(3);
hyperram_reg_control_write(
0 << CSR_HYPERRAM_REG_CONTROL_WRITE_OFFSET |
1 << CSR_HYPERRAM_REG_CONTROL_READ_OFFSET |
2 << CSR_HYPERRAM_REG_CONTROL_ADDR_OFFSET
);
while ((hyperram_reg_status_read() & (1 << CSR_HYPERRAM_REG_STATUS_READ_DONE_OFFSET)) == 0);
config_reg_0 = hyperram_reg_rdata_read();
printf("Configuration Register 0 new : %08lx\n", config_reg_0);
#endif
#if defined(CSR_ETHMAC_BASE) || defined(MAIN_RAM_BASE) || defined(CSR_SPIFLASH_CORE_BASE)